1. Field of the Invention
This invention relates to a wall rack, more particularly to a wall rack with an extensible arm unit and a turnable support frame on which an article can be supported steadily.
2. Description of the Related Art
Referring to FIG. 1, a conventional wall rack (W1) includes a wall mounting member 10 which is to be attached to a wall, and an extensible arm unit 110 which has a first arm 11 and a second arm 12. The first arm 11 has a first end 13 pivoted to the wall mounting member 10 and a second end 13'. The second arm 12 has a first end 14 pivoted to the second end 13' of the first arm 11 and a second end formed with a pivot seat 17. A turnable support frame 18 is disposed on the pivot seat 17 and has a bar 18' for supporting an article, such as a television, thereon. A pivot shaft 173 passes through the bar 18' and is received in the pivot seat 17 in order to interconnect the bar 18' and the pivot seat 17 so as to permit rotation of the support frame 18 about the axis of the pivot shaft 173 with respect to the pivot seat 17. In this way, the article supported on the support frame 18 can be extended to a desired position and turned to an appropriate orientation by operating the arm unit 110 and the support frame 18. Generally, the pivot shaft 173 and the pivot seat 17 are made of metal and are liable to wear after a period of use. Thus, the worn-out pivot shaft 173 cannot be received steadily in the worn-out pivot seat 17, thereby resulting in vibration of the support frame 18. In this way, the article on the support frame 18 cannot be supported steadily. In addition, because the pivot seat 17 is formed integrally with the second arm 12, replacement of the worn-out pivot seat 17 is difficult and inconvenient to conduct. Therefore, the supporting effect provided by the conventional wall rack (W1) cannot be improved easily.